Flight path generation system and unmanned aerial vehicle

Abstract

This flight path generating system is mounted to an unmanned flying craft, said system comprising an acquisition device for acquiring data about a predetermined flight path, a sensor that measures wind directions and outputs sensor data indicating the wind directions, and a processing device that updates the flight path in accordance with the wind directions indicated by the sensor data.

Description

Technical Field

[0001] The present disclosure relates to a flight path generation system and an unmanned aerial vehicle.

Background Art

[0002] An unmanned aerial vehicle (UAV) is an aircraft that is structurally not capable of carrying a person and can fly by remote control or autopilot. A rotary-wing unmanned aerial vehicle is an unmanned aerial vehicle that obtains lift by using a propeller, i.e., a rotary wing, that rotates around an axis. A small unmanned aerial vehicle (Multi-Rotor UAV) equipped with a plurality of rotary wings is also called a "drone", "multi-rotor", or "multicopter", and is widely used in applications such as aerial photography, surveying, logistics, and agricultural chemical spraying.

[0003] An unmanned aerial vehicle equipped with a sensor for measuring wind speed and wind direction is known. Patent Document 1 describes a technique for controlling the flight of an unmanned aerial vehicle along a flight path based on the wind speed and wind direction measured during the flight of the unmanned aerial vehicle.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When an unmanned aerial vehicle is used for agricultural chemical spraying, it is required to appropriately spray agricultural chemicals on the ground spraying target area where the agricultural chemicals are to be sprayed.

[0006] The present disclosure provides a flight path generation system and an unmanned aerial vehicle that enable appropriate spraying of agricultural chemicals on a spraying target area in a relatively simple manner even when there is wind blowing in the air. [Means for solving the problem]

[0007] In exemplary and non-limiting embodiments, the flight path generation system of the present disclosure is a flight path generation system mounted on an unmanned aerial vehicle, comprising: an acquisition device that acquires data of a predetermined flight path; a sensor that measures wind direction and outputs sensor data indicating the wind direction; and a processing device that updates the flight path according to the wind direction indicated by the sensor data.

[0008] In exemplary and non-limiting embodiments, the unmanned aerial vehicle of this disclosure comprises a plurality of rotors and the flight path generation system described above. [Effects of the Invention]

[0009] According to embodiments of the present disclosure, a flight path generation system is provided that enables the appropriate application of pesticides to a target area in a relatively simple manner, even when there is wind in the upper atmosphere, and an unmanned aerial vehicle equipped with the flight path generation system is provided. [Brief explanation of the drawing]

[0010] [Figure 1A] This is a schematic block diagram showing several examples of rotary drive devices for rotating rotors in an unmanned aerial vehicle equipped with multiple rotors. [Figure 1B] This is a schematic plan view illustrating one basic configuration example of an unmanned aerial vehicle equipped with multiple rotors. [Figure 1C] This is a schematic side view illustrating one basic configuration example of an unmanned aerial vehicle equipped with multiple rotors. [Figure 1D] This is a schematic plan view illustrating another basic configuration example of an unmanned aerial vehicle equipped with multiple rotors. [Figure 2A] This block diagram shows an example of the basic configuration of a battery-powered multirotor. [Figure 2B] This block diagram shows an example of the basic configuration of a series hybrid drive multicopter. [Figure 2C]It is a block diagram showing a basic configuration example of a parallel hybrid drive type multicopter. [Figure 3] It is a diagram schematically showing a flight path set over a field for material spraying. [Figure 4] It is a diagram schematically showing a flight path shifted by Δx1 in the direction opposite to the wind direction. [Figure 5] It is a diagram schematically showing a flight path shifted by Δx2 in the direction opposite to the wind direction. [Figure 6] It is a diagram schematically showing a flight path shifted in the direction opposite to the wind direction of the wind blowing from an oblique direction. [Figure 7] It is a diagram for explaining an example of determining an offset amount for each main part and shifting the main part by the determined offset amount. [Figure 8] It is a diagram schematically showing an example of the spraying situation after the multicopter flies along the changed flight path. [Figure 9] It is a diagram schematically showing an example of a further flight path for spraying materials on the estimated unfinished area. [Figure 10] It is a block diagram showing an example of the hardware configuration of a control device. [Figure 11] It is a schematic diagram showing an example in which a multicopter, an agricultural machine, a server, and a terminal device are connected via a communication network.

Embodiments for Carrying Out the Invention

[0011] An unmanned aerial vehicle having a plurality of rotors includes a rotational drive device that rotates the rotors (hereinafter, may be referred to as "propellers" in some cases). Hereinafter, such an unmanned aerial vehicle is referred to as a "multicopter".

[0012] There are various forms in the configuration of the rotational drive device provided in the multicopter. FIG. 1A is a block diagram schematically showing four examples of the rotational drive device 3 in the present disclosure.

[0013] The first rotary drive device 3A shown in FIG. 1A has a plurality of electric motors (hereinafter referred to as "motors") 14 that rotate a plurality of rotors, and a battery 52 that stores electric power supplied to each motor 14. The battery 52 is a secondary battery such as a polymer lithium-ion battery, for example. Each rotor 2 is connected to the output shaft of the corresponding motor 14 and is rotated by the motor 14. In order to increase the payload and / or flight time, it is necessary to increase the storage capacity of the battery 52. The storage capacity of the battery 52 can be achieved by increasing the size of the battery 52, but increasing the size of the battery 52 causes an increase in weight.

[0014] The second rotary drive device 3B shown in FIG. 1A has a power transmission system 23 mechanically connected to the rotor 2 and an internal combustion engine 7a that applies a driving force (torque) to the power transmission system 23. The power transmission system 23 includes mechanical components such as gears or belts, for example, and transmits the torque of the output shaft of the internal combustion engine 7a to the rotor 2. The internal combustion engine 7a can efficiently generate mechanical energy by burning fuel. Examples of the internal combustion engine 7a may include a gasoline engine, a diesel engine, and a hydrogen engine. Also, the number of internal combustion engines 7a included in the rotary drive device 3B is not limited to one.

[0015] The third rotary drive device 3C shown in FIG. 1A has a plurality of motors 14, a power buffer 9 that stores electric power supplied to each motor 14, a power generation device 8 such as an alternator that generates electric power, and an internal combustion engine 7a that applies mechanical energy for power generation to the power generation device 8. A typical example of the power buffer 9 is a battery such as a secondary battery, but it may also be a capacitor. In the third rotary drive device 3C, even when the storage capacity of the power buffer 9 is not large, the power generation device 8 generates electric power using the driving force (mechanical energy) of the internal combustion engine 7a, so that it is possible to increase the payload and / or flight time. Such a form of drive is called "series hybrid drive". The power generation device 8 and the internal combustion engine 7a in the series hybrid drive are called "range extenders" in order to extend the flight distance of the multicopter.

[0016] The fourth rotary drive unit 3D shown in Figure 1A includes a plurality of motors 14, a power buffer 9 for storing power supplied to each motor 14, a power generation device 8 such as an alternator for generating power, an internal combustion engine 7a for providing driving force to the power generation device 8 for power generation, and a power transmission system 23 for transmitting the driving force generated by the internal combustion engine 7a to the rotor 2 to rotate the rotor 2. At least one of the plurality of rotors 2 is rotated by the internal combustion engine 7a, and the other rotors 2 are rotated by the motors 14. In the fourth rotary drive unit 3D, the mechanical energy generated by the internal combustion engine 7a can be used to rotate the rotor 2 without being converted into electricity, thus increasing the energy utilization efficiency. This type of drive is called a "parallel hybrid drive".

[0017] Figure 1B is a schematic plan view showing one of the basic configuration examples of the multicopter 10. The configuration example in Figure 1B includes the first rotary drive device 3A shown in Figure 1A as the rotary drive device 3. That is, the rotary drive device 3(3A) in this example has a motor 14 and a battery 52. ​​Figure 1C is a schematic side view showing the multicopter.

[0018] The multicopter 10 shown in Figures 1B and 1C comprises multiple rotors 2, a main body 4, and a frame 5 that supports the rotors 2 and the main body 4. The frame 5 supports the main body 4 at its center and rotatably supports the multiple rotors 2 with multiple arms 5A extending outward from the center. A motor 14 for rotating the rotors 2 is provided near the tip of each arm 5A.

[0019] In the example shown in Figure 1B, the multicopter 10 is a quadcopter equipped with four rotors 2. Rotors 2 located on one diagonal rotate in the same direction (clockwise or counterclockwise), while rotors 2 located on different diagonal lines rotate in opposite directions.

[0020] The aircraft body 4 includes a control device 4a that controls the operation of devices and components mounted on the multicopter 10, a group of sensors 4b connected to the control device 4a, a communication device 4c connected to the control device 4a, and a battery 52.

[0021] The control device 4a may include, for example, a flight control device such as a flight controller and a higher-level computer (companion computer). The companion computer can perform advanced computational processing such as image processing, obstacle detection, and obstacle avoidance based on sensor data acquired by the sensor group 4b.

[0022] The sensor group 4b may include an acceleration sensor, an angular velocity sensor, a geomagnetic sensor, a barometric pressure sensor, an altitude sensor, a temperature sensor, a wind speed sensor, a wind direction sensor, a flow rate sensor, an imaging device, a laser sensor, an ultrasonic sensor, an obstacle contact sensor, and a GNSS (Global Navigation Satellite System) receiver. The acceleration sensor and angular velocity sensor may be mounted on the aircraft body 4 as components of an IMU (Inertial Measurement Unit), for example. Examples of laser sensors may include a laser rangefinder used to measure the distance to the ground, and a two-dimensional or three-dimensional LiDAR.

[0023] The communication device 4c may include a wireless communication module for transmitting and receiving signals to and from a transmitter or ground control station (GCS) on the ground via an antenna, and a mobile communication module that utilizes a cellular communication network. The communication device 4c may receive signals such as control commands transmitted from the ground and transmit sensor data such as image data acquired by the sensor group 4b as telemetry information. The communication device 4c may also have the function of communicating with other multirotors and the function of satellite communication. The control device 4a can be connected to a computer on the cloud by the communication device 4c. Some or all of the functions of the companion computer may be performed by the computer on the cloud.

[0024] The battery 52 is a rechargeable battery that can store power by charging and supply power to the motor 14 by discharging. Through the action of the battery 52 and the multiple motors 14, multiple rotors 2 are driven to rotate, making it possible to generate the desired thrust.

[0025] Each of the multiple rotors 2 generally has multiple blades with a fixed pitch angle and generates thrust through rotation. The pitch angle may be variable. Not all of the multiple rotors 2 need to have the same diameter (propeller diameter); one or more rotors 2 may have a larger diameter than the others. The thrust generated by the rotating rotors 2 (static thrust) is generally proportional to the cube of the rotor's diameter. For this reason, when rotors 2 with different diameters are provided, the rotor 2 with a relatively larger diameter may be called the "main rotor," and the rotor 2 with a relatively smaller diameter may be called the "sub-rotor." Regardless of the size of the diameter, the configuration of the rotary drive unit 3 may include a rotor 2 with a relatively large thrust and a rotor 2 with a relatively small thrust. In that case, the rotor 2 with a relatively large thrust may be called the "main rotor," and the rotor 2 with a relatively small thrust may be called the "sub-rotor." For example, a rotor 2 that generates a relatively large thrust per revolution may be called the "main rotor," and a rotor 2 that generates a relatively small thrust per revolution may be called the "sub-rotor." In one example, the main rotor may be positioned inward of the sub-rotors. In other words, each rotor 2 may be positioned such that the distance from the center of the aircraft to the axis of rotation of each main rotor is shorter than the distance from the center of the aircraft to the axis of rotation of each sub-rotor.

[0026] In this example, the rotary drive unit 3 has a plurality of motors 14. As mentioned above, the rotary drive unit 3 may also include an internal combustion engine 7a.

[0027] Figure 1D is a schematic plan view showing a basic configuration example of a multicopter 10 equipped with a second rotary drive unit 3B as the rotary drive unit 3. In the example shown in Figure 1D, the internal combustion engine 7a is supported by the aircraft body 4. In this example, the driving force generated by the internal combustion engine 7a is transmitted to multiple rotors 2 by multiple power transmission systems 23, causing each rotor 2 to rotate. The control device 4a can change the rotational speed of each individual rotor 2 by controlling each power transmission system 23.

[0028] In a "parallel hybrid drive" configuration, where some of the multiple rotors 2 are rotated by an internal combustion engine 7a and other rotors 2 are rotated by a motor 14, the internal combustion engine 7a and battery 52 are supported by the main body 4. At least one of the multiple rotors 2 is connected to the internal combustion engine 7a via a power transmission system 23, and the other rotors 2 are connected to the motor 14.

[0029] In such a parallel hybrid drive, the diameter of one or more rotors 2 rotated by the internal combustion engine 7a may be larger than the diameter of the other rotors 2 rotated by the motor 14. In other words, the internal combustion engine 7a may be used to rotate the main rotor, and the motor 14 may be used to rotate the sub-rotor. In such a case, the main rotor is mainly used for thrust generation, and the sub-rotor is used for thrust generation and attitude control. The main rotor may also be called the "booster rotor," and the sub-rotor may be called the "attitude control rotor."

[0030] In a parallel hybrid drive system, the internal combustion engine 7a is used for both thrust generation and power generation. It is also possible to balance thrust generation and power generation by selectively transmitting the driving force (torque) generated by the internal combustion engine to one or both of the rotor and / or the power generation device.

[0031] The inclusion of an internal combustion engine 7a in the multirotor, which generates thrust and / or electricity, contributes to increased payload and flight time. Attitude control of the multirotor is preferably performed by rotating the propellers with motors that have superior response characteristics to those of an internal combustion engine. Therefore, in applications requiring precise attitude control of the multirotor, employing a parallel hybrid or series hybrid drive is desirable to increase payload and flight time.

[0032] Increased payload and flight time could further expand the applications of multicopters. For example, in agriculture, multicopters are currently being used for pesticide spraying or monitoring crop growth, but by attaching various ground implements (hereinafter sometimes simply referred to as "implements") to the multicopter, it will be possible to perform various agricultural tasks from the air. Agricultural implements are sometimes called "implements." Examples of implements may include sprayers for spraying pesticides on crops, mowers, seeders, spreaders, rakes, balers, harvesters, plows, harrows, or rotary tillers. Work vehicles such as tractors are not included in the definition of "implements" in this disclosure.

[0033] In the example shown in Figure 1C, the multicopter 10 is coupled with an implement 200 capable of spraying, for example, pesticides or fertilizers onto or within a field. Increased payload and flight time allow for larger and / or more multifunctional implements 200. For example, by changing the implement 200 coupled to the multicopter 10, it becomes possible to perform a variety of ground operations (agricultural work), including liquid and granular application, fertilization, thinning, weeding, transplanting, direct seeding, and harvesting. The implement 200 may be equipped with mechanisms such as a robotic hand. In that case, a single implement 200 can perform a variety of ground operations. Furthermore, if the implement 200 has a sufficiently large space to accommodate materials, it can also be used to transport agricultural materials or harvested produce over a wide area.

[0034] In the example shown in Figure 1C, the multicopter 10 is equipped with a power supply device 76. The power supply device 76 is a device that supplies power to the work implement 200 from a drive energy source such as a battery 52 or a power generator 8 provided by the multicopter 10. Various functions of the work implement 200 can be performed by this power. The work implement 200 is equipped with actuators such as motors that are operated by the power obtained from the power supply device 76 of the multicopter 10. Preferably, the work implement 200 is equipped with a battery for storing power.

[0035] Figure 2A is a block diagram showing a basic configuration example of a battery-powered multicopter 10. The battery-powered multicopter 10 includes multiple rotors 12, multiple motors 14 that rotate each of the multiple rotors 12, multiple ESCs (Electric Speed ​​Controllers) 16 each having a motor drive circuit that drives each of the multiple motors 14, a battery 52 that supplies power to the corresponding motors 14 via each ESC 16, a control device 4a for controlling the attitude and performing flight by controlling the multiple ESCs 16, a sensor group 4b, a communication device 4c, and a power supply device 76 electrically connected to the battery 52. ​​Rotor 12 is an example of rotor 2. Devices such as the control device 4a, sensor group 4b, and communication device 4c are connected to each other so that they can communicate with one another, for example, via a CAN (Controller Area Network) bus. In Figure 2A, for simplicity, the rotors 12, motors 14, and ESCs 16 are each shown as one block, but the number of rotors 12, motors 14, and ESCs 16 can be multiple. This point also applies to Figures 2B and 2C.

[0036] The control device 4a can wirelessly receive control commands from, for example, a ground station 6 located on the ground via the communication device 4c. The number of ground stations 6 is not limited to one, but may be distributed across multiple locations. The communication device 4c can also wirelessly receive control commands from the control device of a pilot on the ground. The control device 4a may have the function of automatically or autonomously performing takeoff, flight, obstacle avoidance, and landing operations based on sensor data obtained from the sensor group 4b.

[0037] The control device 4a may be configured to communicate with the work machine 200 connected to the power supply device 76 and to obtain signals from the work machine 200 indicating the status of the work machine 200. The control device 4a may also provide signals to the work machine 200 to control its operation. Furthermore, the work machine 200 may generate signals instructing the operation of the multicopter 10 and transmit them to the control device 4a. Such communication between the control device 4a and the work machine 200 can be conducted via wire or wireless connection.

[0038] Figure 2B is a block diagram showing an example of the basic configuration of a series hybrid drive multicopter 10. Similar to a battery-powered multicopter 10, the series hybrid drive multicopter 10 comprises multiple rotors 12, multiple motors 14, multiple ESCs 16, a control device 4a, a sensor group 4b, and a communication device 4c. The illustrated series hybrid drive multicopter 10 further includes an internal combustion engine 7a, a fuel tank 7b for storing fuel for the internal combustion engine 7a, a power generator 8 driven by the internal combustion engine 7a to generate electricity, a power buffer 9 for temporarily storing the electricity generated by the power generator 8, and a power supply device 76 electrically connected to the power buffer 9. The power buffer 9 is, for example, a battery such as a secondary battery. The electricity generated by the power generator 8 is supplied to the motors 14 via the power buffer 9 and the ESCs 16. The electricity generated by the power generator 8 can also be supplied to the work machine 200 via the power supply device 76.

[0039] Figure 2C is a block diagram showing an example of the basic configuration of a parallel hybrid drive type multicopter 10. Similar to a series hybrid drive type multicopter 10, the parallel hybrid drive type multicopter 10 includes multiple rotors 12, multiple motors 14, multiple ESCs 16, a control device 4a, a sensor group 4b, a communication device 4c, an internal combustion engine 7a, a fuel tank 7b, a power generator 8, a power buffer 9, and a power supply device 76. The parallel hybrid drive type multicopter 10 further includes a drivetrain 27 that transmits the driving force of the internal combustion engine 7a, and rotors 22 that rotate by receiving the driving force from the internal combustion engine 7a via the drivetrain 27. Rotor 22 is an example of rotor 2. There may be one rotor 22 connected to the drivetrain 27 and rotating, or there may be two or more rotors 22.

[0040] In a parallel hybrid drive multicopter 10, the internal combustion engine 7a not only drives the power generator 8 to generate electricity, but also mechanically transmits energy to the rotor 22 to rotate it. On the other hand, in a series hybrid drive multicopter 10, all rotors 12 rotate using the electricity generated by the power generator 8. Therefore, in a series hybrid drive multicopter 10, if the power generator 8 is, for example, a fuel cell, the internal combustion engine 7a is not an essential component.

[0041] A multicopter according to the embodiments of this disclosure is equipped with a flight path generation system comprising an acquisition device for acquiring predetermined flight path data, a sensor for measuring wind direction and outputting sensor data indicating wind direction, and a processing device for updating the flight path according to the wind direction indicated by the sensor data. The flight path is typically defined by a group of waypoints, each containing latitude and longitude information. The waypoints may further include altitude information.

[0042] The multicopter according to the embodiments of this disclosure is not limited to a quadcopter, but may be, for example, a hexacopter with six rotors, or an octocopter with eight rotors. The control device 4a described above may be programmed to enable autonomous flight of the multicopter. In that case, the multicopter can fly autonomously along a predetermined flight path.

[0043] This specification describes, but is not limited to, examples of using the updating or modification of flight paths in response to wind direction primarily for material spraying by multicopters. A multicopter according to the embodiments of this disclosure may further be equipped as an implement 200 for spraying granular or liquid agricultural materials (hereinafter simply referred to as "materials") onto the ground, as shown in Figure 1C. Examples of materials include liquid or granular chemicals such as herbicides or insecticides, water, and seeds.

[0044] A processing device is a device comprising one or more semiconductor integrated circuits (e.g., a processor).

[0045] The acquisition device in this embodiment is, for example, the communication device 4c described above. The acquisition device acquires predetermined flight path data from, for example, a cloud server. The acquisition device can further store the acquired flight path data in a storage device. The storage device may be, for example, a semiconductor memory, a magnetic storage device, or an optical storage device, or a combination thereof.

[0046] The sensor measures wind direction. The sensor may also be configured to measure wind speed. Examples of sensors include wind direction sensors, wind speed sensors, and wind speed and wind direction sensors configured to measure both wind direction and wind speed.

[0047] Figure 3 schematically shows a flight path P set above field F for material distribution. The flight path P shown in Figure 3 is the initial flight path determined in advance. For reference, Figure 3 shows mutually orthogonal X and Y axes. The X and Y axes are located in a horizontal plane perpendicular to the vertical direction. For example, the direction the X-axis arrow points is south, and the direction the Y-axis arrow points is west.

[0048] When agricultural workers, for example, use terminal devices or mobile terminals to formulate work plans or multirotor flight plans, they determine the flight path considering factors such as the type of multirotor and the shape of the field. As shown in Figure 3, a flight path can be created by displaying field F (a map showing field F, and the outline of field F) on the screen of a terminal device or mobile device, and drawing a flight path on field F.

[0049] In embodiments of this disclosure, the flight path may further be determined by taking into account at least one of the type, size, and weight of the materials. Examples of agricultural workers include field managers, workers performing agricultural work in the field, and operators remotely controlling the multicopter. The data of the flight path thus determined may be transmitted, for example, from a terminal device or mobile device to a cloud server and temporarily stored in cloud storage on the cloud server. The multicopter can download the flight path data over the network by accessing the cloud server, for example, when it is powered on. The downloaded data is stored in the flight path generation system or the multicopter's storage device.

[0050] As illustrated in Figure 3, the flight path P includes a plurality of main sections 91 and a plurality of sub-sections 92. Each of the plurality of main sections 91 includes a straight section. Each main section 91 may include a curved section in addition to the straight section. In the illustrated example, a plurality of main sections 91 are shown, each including a straight section parallel to the Y-axis and not including a curved section. The plurality of main sections 91 are positioned at equal intervals from each other along the X-axis. Each of the plurality of sub-sections 92 includes an arc-shaped section for the multicopter 10 to turn. The plurality of sub-sections 92 are located at both ends of the plurality of main sections 91 and connect the plurality of main sections 91.

[0051] The flight path P includes a starting point S where the multicopter 10 begins flying along the flight path P, and an ending point E where the multicopter 10 ends flying along the flight path P. As shown in Figure 3, the flight path P is set within a predetermined work area F1 within the area representing the field F. The work area F1 is, for example, an area where crops are planted or an area where crops are planned to be planted. The work area F1 can be determined by operating a terminal device or mobile terminal, and can be determined by, for example, shifting the outline of the field F inward by several tens of centimeters to several meters through a predetermined operation.

[0052] The multicopter 10 spreads material over the work area F1 by flying back and forth along a flight path P from a starting point S to an ending point E, following multiple main sections 91 parallel to the Y-axis. For the sake of explanation, the area where the material is spread and the work area F1 are the same, so the area in the spreading operation will be referred to as the "spreading target area 95". The spreading target area 95 is the area within field F where the material is spread. For example, crops are planted in the spreading target area 95.

[0053] When a multicopter flies along a predetermined initial flight path, if the wind at high altitude is strong, the material sprayed from the multicopter into the air will be affected by the wind. As a result, it becomes difficult to properly spray the material onto the intended target area. In the embodiments of this disclosure, the processing device determines whether or not to update the initial flight path data based on the wind speed measured by a sensor at a measurement point above field F before the multicopter 10 reaches the starting point S. Specifically, the wind speed and wind direction are measured at a measurement point above field F before the multicopter 10 begins flying along the flight path P. It is preferable that the wind speed and wind direction are measured at multiple measurement points above field F. For example, the processing device can determine the average or cumulative value of the wind speed measured at multiple measurement points above field F and determine the wind speed above field F (representative value of wind speed) from that average or cumulative value. Similarly, the processing device can determine the wind direction above field F (representative wind direction) from the wind directions measured at multiple measurement points above field F. The multiple measurement points include, for example, points above the center of the spraying area 95 and points above the corners that define the outline of the spraying area 95.

[0054] As another example, the multicopter 10 may fly along the initial flight path before material spreading and measure wind speed and direction. Such a flight is called a pre-flight before material spreading. During the pre-flight, the multicopter 10 may measure wind speed and direction each time it turns in a sub-section 92 after flying along one main section 91, for example. Alternatively, the multicopter 10 may measure wind speed and direction at multiple measurement points while flying along one main section 91. In this way, the multicopter 10 can collect wind speed and direction data at multiple measurement points above field F.

[0055] In this specification, not only the wind speed measured by the sensor at a measurement point above the field, but also representative values ​​of wind speed obtained from wind speeds measured by the sensor at multiple measurement points above the field, are referred to as "wind speed measured by the sensor" or simply "measured wind speed."

[0056] In the embodiments of this disclosure, the processing device adopts a flight path indicated by data pre-stored in a storage device if the wind speed measured by the sensor is below a threshold, and updates the flight path data stored in the storage device if the wind speed measured by the sensor is equal to or greater than the threshold. The threshold can be set, for example, in the range of 0 m / s to 1.0 m / s. The threshold can also be set by an agricultural worker, for example, using a terminal device or a mobile terminal. When the threshold is set to 0 m / s, the processing device will update the flight path data according to the wind speed.

[0057] The processing device updates the flight path according to the wind direction measured by the sensor, or a representative wind direction determined from the wind direction measured by the sensor. In this specification, not only the wind direction measured by the sensor, but also the representative wind direction determined from the wind direction measured by the sensor are referred to as "wind direction measured by the sensor" or simply "measured wind direction". In embodiments of this disclosure, the processing device updates the flight path by shifting at least one of the plurality of main parts 91 in the opposite direction to the wind direction according to the wind direction measured by the sensor.

[0058] Figure 4 schematically shows a flight path P shifted by Δx1 in the opposite direction to the wind direction. In Figure 4, the starting point Sa of the original flight path P before the change (or offset) is shown as a white circle, and the starting point Sb of the flight path P after the change (or offset) is shown as a black circle. In the example shown in Figure 4, it is assumed that a wind W1 with a wind speed above a threshold is blowing above field F in the direction of the arrow on the X axis.

[0059] Before the multicopter passes the starting point, the sensors measure the wind speed and direction. In other words, before the multicopter begins flying along the original or modified flight path, the sensors measure the wind speed and direction. In the example shown in Figure 4, the processing unit determines that the wind speed measured by the sensors is above a threshold.

[0060] Next, the processing unit may update the flight path by shifting all of the multiple main sections 91 in the opposite direction to the wind direction measured by the sensor. Shifting the flight path P in the opposite direction to the wind direction is equivalent to shifting the flight path P to the upwind side, which in the example shown in Figure 4 means shifting the flight path P in the opposite direction to the direction of the arrow on the X axis.

[0061] The processing unit may determine, in accordance with the measured wind speed, an offset amount to shift at least one of the multiple main parts 91 in the opposite direction to the wind direction. The processing unit increases the offset amount as the wind speed increases and decreases the offset amount as the wind speed decreases.

[0062] In the example shown in Figure 4, the processing unit determines an offset amount Δx1 for shifting each of the multiple main sections 91 in the opposite direction to the wind direction, according to the wind speed measured before material dispersal. The offset amount Δx1 corresponds to the distance between the original starting point Sa and the modified starting point Sb in the X-axis direction. In this way, the processing unit can shift the entire flight path P by moving the original starting point Sa by Δx1 in the opposite direction to the wind direction. In other words, the processing unit can shift the entire flight path P by moving each main section 91 by Δx1 in the opposite direction to the wind direction.

[0063] Figure 5 schematically shows a flight path P shifted by Δx2 in the opposite direction to the wind direction. In Figure 5, the starting point Sa of the original flight path P is shown as a white circle, and the starting point Sb of the modified flight path P is shown as a black circle. In the example shown in Figure 5, it is assumed that a wind W2, which has a wind speed above a threshold and is stronger than wind W1 shown in Figure 4, is blowing above field F in the direction of the arrow on the X axis. The wind speed of wind W2 is greater than the wind speed of wind W1. As explained with reference to Figure 4, the sensor measures the wind speed and wind direction above field F before the multicopter passes the starting point. In the example shown in Figure 5, the processing unit determines that the measured wind speed is above the threshold.

[0064] Next, the processing unit can update the flight path P by shifting all of the multiple main sections 91 in the opposite direction to the wind direction measured by the sensor. At this time, the processing unit determines an offset amount Δx2 for shifting each of the multiple main sections 91 in the opposite direction to the wind direction, according to the wind speed measured before material dispersal. The offset amount Δx2 corresponds to the distance between the starting point Sa before the change and the starting point Sb after the change in the X-axis direction. The offset amount Δx2 is greater than the offset amount Δx1. In this way, the processing unit can shift the entire flight path P by moving each main section 91 by Δx2 in the opposite direction to the wind direction.

[0065] Figure 6 schematically shows a flight path P shifted in the opposite direction to the wind direction of a wind blowing from an oblique direction. In Figure 6, the starting point Sa of the original flight path P is shown as a white circle, and the starting point Sb of the modified flight path P is shown as a black circle. In the example shown in Figure 6, it is assumed that a wind W3 with a wind speed above a threshold is blowing from an oblique direction intersecting the X-axis or Y-axis direction, that is, from a direction intersecting the multiple main sections 91. As explained with reference to Figure 4, before the multicopter passes the starting point, the sensor measures the wind speed and wind direction above the field F. In the example shown in Figure 6, the processing unit determines that the measured wind speed is above a threshold.

[0066] Next, the processing unit can update the flight path P by shifting all of the multiple main sections 91 in the opposite direction to the wind direction measured by the sensor. At this time, the processing unit determines an offset amount Δx3 for shifting each of the multiple main sections 91 in the X-axis direction according to the X-axis component of the wind speed W3. Furthermore, the processing unit determines an offset amount Δy3 for shifting each of the multiple main sections 91 in the Y-axis direction according to the Y-axis component of the wind speed W3. The offset amount Δx3 corresponds to the distance between the starting point Sa before the change and the starting point Sb after the change in the X-axis direction, and the offset amount Δy3 corresponds to the distance between the starting point Sa before the change and the starting point Sb after the change in the Y-axis direction. In this way, even when the wind is blowing from an oblique direction, the processing unit can shift the entire flight path P by moving each main section 91 by Δx3 and Δy3 in the X-axis and Y-axis directions, respectively, in the opposite direction to the wind direction.

[0067] In the example described above, the entire flight path is shifted according to wind speed and direction measured by sensors before the multicopter passes the starting point of the flight path, or before the multicopter begins flying along the flight path, but the disclosure is not limited thereto. As described below, the processing unit may determine an offset amount and a shift direction for each main section according to the wind speed and direction measured at multiple measurement points while the multicopter is flying along one main section, and shift each main section according to the determined offset amount and shift direction.

[0068] Figure 7 illustrates an example of determining an offset amount for each main section and shifting the main sections by the determined offset amount. In Figure 7, the main section 91a-1 connected to the starting point Sa, the main section 91a-2 connected to the main section 91a-1 via a sub-section, and the main section 91a-3 connected to the main section 91a-2 via a sub-section are each shown as dashed lines. The main section 91b-1 connected to the starting point Sb, the main section 91b-2 connected to the main section 91b-1 via a sub-section, and the main section 91b-3 connected to the main section 91b-2 via a sub-section are each shown as dashed lines. The three main sections 91a-1, 91a-2, and 91a-3 correspond to the three main sections 91b-1, 91b-2, and 91b-3, respectively.

[0069] Before the multicopter begins flying along each main section, sensors may measure the wind speed for each main section. The processing unit may determine an offset amount for each main section based on the measured wind speed and update the flight path by offsetting each main section in the opposite direction to the wind by the determined offset amount. For example, the processing unit may determine the offset amount for the next main section based on the average or cumulative value of wind speeds measured at multiple measurement points while the multicopter is flying along one main section, and shift that main section in the opposite direction to the wind by the determined offset amount.

[0070] In the example shown in Figure 7, assume that the wind is blowing in the direction of the arrow on the X axis. First, a sensor measures the wind speed W1 blowing in the upper atmosphere before the multicopter begins flying along its flight path. The processing unit determines an offset amount Δx1 according to the measured wind speed W1, and shifts the main section 91a-1 in the opposite direction to the arrow on the X axis by the determined offset amount Δx1. As a result, the main section 91a-1 in the flight path is changed to the main section 91b-1.

[0071] Next, while the multicopter flies along the main section 91b-1, sensors measure the wind speed of the wind W2 blowing in the upper atmosphere at multiple measurement points. In the example shown in Figure 7, the wind speed of wind W2 is greater than the wind speed of wind W1. Based on the average or integrated value of the wind speed of wind W2 measured at multiple measurement points, the processing unit determines an offset amount Δx2 that is greater than the offset amount Δx1, and shifts the main section 91a-2 in the opposite direction to the X-axis arrow by the determined offset amount Δx2. As a result, the main section 91a-2 in the flight path is changed to the main section 91b-2.

[0072] Next, while the multicopter flies along the main section 91b-2, sensors measure the wind speed of the wind W3 blowing in the upper atmosphere at multiple measurement points. In the example shown in Figure 7, the wind speed of wind W3 is greater than the wind speed of wind W2. Based on the average or integrated value of the wind speed of wind W3 measured at multiple measurement points, the processing unit determines an offset amount Δx3 that is greater than the offset amount Δx2, and shifts the main section 91a-3 in the opposite direction to the X-axis arrow by the determined offset amount Δx3. As a result, the main section 91a-3 in the flight path is changed to the main section 91b-3.

[0073] In this way, the processing device may shift each of the multiple main sections included in the flight path by an offset amount determined according to the wind speed measured by the multicopter while flying along the previous main section. The processing device can update the entire flight path by repeatedly performing this process for each of the multiple main sections. In some fields, there may be areas where the application of materials is prohibited (no-spray zones). This method makes it possible to change the flight path according to the offset amount and shift direction determined for each main section. Therefore, flying the multicopter along the changed flight path is advantageous in suppressing the application of materials to the no-spray zones.

[0074] According to the flight path updating method of the embodiment of this disclosure, a processing unit determines the shift direction and offset amount of the flight path or the main portion included in the flight path based on wind speed and wind direction measured by sensors before the multicopter begins flying along the flight path. Since such calculations do not particularly require real-time processing required for control such as attitude control during the flight of the multicopter, the computational load on the control unit can be reduced. In this way, it is possible to change or update the flight path in accordance with wind speed and wind direction with relatively simple processing.

[0075] In the multicopter according to the embodiments of this disclosure, a spreader for scattering materials on the ground can be attached as a work machine 200, as shown in Figure 1C. The processing device can determine an offset amount to shift at least one of a plurality of main parts in the opposite direction to the wind direction, taking into account at least one of the type, size, and weight of the material. The processing device in the embodiments of this disclosure can determine the offset amount based on at least one of the type, size, and weight of the material and the wind speed.

[0076] Even with the same wind speed and direction, the horizontal distance a material reaches the ground after being sprayed from the air, or the resulting ground dispersion, can vary depending on the type, size, and weight of the material. By considering at least one of the material's type, size, and weight when determining the offset amount, the flight path can be more precisely adjusted in response to wind speed and direction. As a result, the accuracy of material spraying can be improved, and spraying operations can be carried out more efficiently.

[0077] A multicopter according to the embodiments of this disclosure may further include a sensing device for sensing the spraying status of a material by a sprayer. Examples of the sensing device include a LiDAR and an imaging device. The sensing device acquires sensing data indicating the spraying status after the multicopter has flown along the modified flight path. The spraying status can be estimated, for example, by applying image analysis to images acquired by the imaging device. Alternatively, the spraying status can be estimated from wind speed, wind direction, and offset amounts relative to each main section or the entire flight path, measured while the multicopter is flying along the flight path.

[0078] The wind speed and / or direction measured by sensors before the multicopter begins flying along its flight path may differ from the wind speed and / or direction actually measured as the multicopter flies along each main section of the flight path. Furthermore, even while the multicopter is flying along the same main section, the wind speed and / or direction may change depending on the section of the main part. As a result, if the multicopter flies along a modified flight path, there is a possibility of uneven distribution of materials to the field.

[0079] Figure 8 schematically illustrates an example of the dispersal situation after a multirotor has flown along a modified flight path. In Figure 8, two adjacent main sections 91-1 and 91-2, which are part of the multiple main sections 91 included in the flight path, are shown with dashed lines. Consider the case where, while the multirotor is flying along main section 91-1, the wind speed measured in sections Z1 and Z3 of main section 91-1 differs from the wind speed measured in section Z2. In the illustrated example, the wind temporarily weakens in section Z2, and the wind speed measured in section Z2 is lower than the wind speed measured in section Z1 or Z3. Therefore, the reach of the material dispersed in the X-axis direction while the multirotor is flying through section Z2 is lower than the reach of the material dispersed in the X-axis direction while the multirotor is flying through section Z1 or Z3. In the example shown in Figure 8, the size of the completed spraying area 95-2 within the target spraying area 95 is smaller than the size in the X-axis direction of the completed spraying areas 95-1 and 95-3 within the target spraying area 95. As a result, unevenness occurs in the degree of material distribution, and an incomplete area 96-1 is created within the target spraying area 95 (the entire area) on the ground where the material is to be distributed.

[0080] Similarly, consider the case where, while the multicopter is flying along the main section 91-2, the wind speed measured in section Z4 of the main section 91-2 differs from the wind speed measured in section Z5. In the illustrated example, the wind temporarily weakens in section Z4, and the wind speed measured in section Z4 is lower than the wind speed measured in section Z5. Therefore, the reach of the material scattered in the X-axis direction while the multicopter is flying through section Z4 is smaller than the reach of the material scattered in the X-axis direction while the multicopter is flying through section Z5. In the example shown in Figure 8, the size of the completed scattering area 95-4 within the scattering target area 95 in the X-axis direction is smaller than the size of the completed scattering area 95-5 within the scattering target area 95. As a result, an incomplete area 96-2 is created within the scattering target area 95 where scattering has not been completed.

[0081] The processing device can estimate the ground geographic coordinates and / or size of such incomplete areas that may exist within the target area 95 by, for example, applying image analysis to image data output from an imaging device. Alternatively, the processing device can estimate the ground geographic coordinates and / or size of the incomplete areas from, for example, latitude and longitude information included in the flight path, wind speed and direction measured while the multicopter is flying along the flight path, and offset amounts relative to each main part or the entire flight path.

[0082] The processing unit may generate additional flight paths for dispersing the material over the estimated incomplete areas and fly a multicopter along these additional flight paths. Figure 9 schematically shows an example of additional flight paths for dispersing the material over the estimated incomplete areas. In the example shown in Figure 9, there are three incomplete areas 96-1, 96-2, and 96-3 within the ground-based target area 95 where dispersing has not been completed. In this case, the processing unit may generate additional flight paths for redispersing the material over the three incomplete areas 96-1, 96-2, and 96-3 and fly a multicopter along these additional flight paths. This makes it possible to reduce uneven material dispersal that may occur due to wind, or to reduce the proportion of incomplete areas within the overall target area. In other words, it is possible to suppress double dispersal of material over completed areas when redispersing is necessary.

[0083] The sprayer may be equipped with a nozzle that has an angle adjustment mechanism for adjusting the direction in which the material is sprayed into the air. While the multicopter is flying along its flight path, sensors may periodically measure wind speed and direction, and the angle adjustment mechanism may be controlled according to the measurement results to adjust the direction in which the material is sprayed in real time. Alternatively, one main part of the flight path may be divided into multiple straight sections, and the wind speed and direction measurements taken for each section may be fed back sequentially to update the flight path. This makes it possible to set a precise flight path according to wind speed and direction, and furthermore, by combining such flight path setting with the control of the nozzle angle adjustment mechanism, the accuracy of material spraying can be improved.

[0084] As described above, according to the embodiments of this disclosure, optimization of material dispersal by a multicopter considering wind speed and wind direction is achieved, and further rationalization of material dispersal can be achieved by considering at least one of the type, size, and weight of the material.

[0085] The control device 4a in the embodiments of this disclosure may be implemented by a digital computer system programmed to perform the aforementioned processes.

[0086] Figure 10 is a block diagram showing an example of the hardware configuration of the control device 4a. The control device 4a comprises a processing unit 34, a ROM (Read Only Memory) 35, a RAM (Random Access Memory) 36, a storage device 37, and a communication interface 38. These components are interconnected via a bus 39. The bus 39 is, for example, a CAN (Controller Area Network) bus.

[0087] The processing unit 34 is a device comprising one or more semiconductor integrated circuits (e.g., processors). A processor is also called a central processing unit (CPU) or microprocessor. The processor sequentially executes computer programs stored in the ROM 35 to perform the aforementioned processing. The term "processor" is broadly interpreted to include FPGAs (Field Programmable Gate Arrays), GPUs (Graphic Processor Units), ASICs (Application Specific Integrated Circuits), or ASSPs (Application Specific Standard Products) equipped with a CPU.

[0088] ROM35 can be, for example, writable memory (e.g., PROM), rewritable memory (e.g., flash memory), or read-only memory. ROM35 stores programs that control the operation of the processor. ROM35 does not need to be a single recording medium; it can be a collection of multiple recording media. Some of these collections may be removable memory.

[0089] RAM36 provides a workspace for temporarily unpacking programs stored in ROM35 during boot-up. RAM36 does not need to be a single storage medium; it can be a collection of multiple storage mediums.

[0090] The communication interface 38 is an interface for communication between the control device 4a and other electronic components or electronic control units (ECUs). For example, the communication interface 38 can perform wired communication compliant with various protocols. The communication interface 38 may also perform wireless communication compliant with the Bluetooth® standard and / or the Wi-Fi® standard. Both standards include wireless communication standards that utilize the 2.4GHz frequency band.

[0091] The storage device 37 may be, for example, a semiconductor memory, a magnetic storage device, or an optical storage device, or a combination thereof. The storage device 37 can store, for example, map data useful for the autonomous flight of the multicopter 10, flight path data, and various sensor data acquired by the multicopter 10 during flight.

[0092] The processing unit 34 may function as the processing unit for the aforementioned flight path generation system, and the storage device 37 may function as the storage device for the flight path generation system.

[0093] As mentioned above, the control device 4a may include, for example, a flight control device such as a flight controller and a higher-level computer (companion computer). The companion computer may perform the necessary processes for updating the flight path and provide flight commands from the companion computer to the flight controller or flight path generation system based on the results of these processes. In addition, some or all of the functions of the electronic equipment such as the control device 4a mounted on the multicopter 10 or the flight path generation system may be implemented by one or more servers (computers) 500 or terminal devices (including portable and fixed types) 600 connected to the communication device 4c of the multicopter 10 via a communication network N, as shown in Figure 11. An agricultural machine 700 such as a tractor may be connected to such a communication network N, and communication may take place between the multicopter 10 and the agricultural machine 700. Some of the data used for processing by the control device 4a and control signals for the multicopter 10 may be provided from the agricultural machine 700 to the multicopter 10 via the communication network N.

[0094] The systems providing the various functions in the embodiments can also be retrofitted to multicopters that do not possess those functions. Such systems can be manufactured and sold independently of the multicopters. Computer programs used in such systems can also be manufactured and sold independently of the multicopters. Computer programs can be provided, for example, by being stored in a computer-readable non-temporary storage medium. Computer programs can also be provided by download via telecommunications lines (e.g., the Internet).

[0095] This specification discloses solutions described in the following sections.

[0096] [Item 1] A flight path generation system installed on an unmanned aerial vehicle, An acquisition device that acquires data on a predetermined flight path, A sensor that measures wind direction and outputs sensor data indicating the wind direction, A processing device that updates the flight path according to the wind direction indicated by the sensor data, A flight path generation system equipped with the following features.

[0097] [Item 2] The aforementioned flight path includes multiple main sections and multiple sub-sections, each of which connects the main sections to one another. The flight path generation system according to item 1, wherein the processing device updates the flight path by shifting at least one of the plurality of main parts in the opposite direction to the wind direction indicated by the sensor data.

[0098] [Item 3] Each of the aforementioned multiple main sections includes a straight section, as described in item 2, in the flight path generation system.

[0099] [Item 4] The aforementioned flight path includes a starting point that causes the unmanned aircraft to begin flying along the aforementioned flight path. The sensor measures the wind direction before the unmanned aerial vehicle passes the starting point. The flight path generation system according to item 2 or 3, wherein the processing device updates the flight path by shifting all of the plurality of main parts in the opposite direction to the wind direction according to the measured wind direction.

[0100] [Item 5] The aforementioned sensor is configured to further measure wind speed, The flight path generation system according to item 2 or 3, wherein the processing device determines an offset amount for shifting at least one of the plurality of main parts in the direction opposite to the wind direction, according to the wind speed.

[0101] [Item 6] Before the unmanned aerial vehicle begins flying along each of the multiple main parts, the sensor measures the wind speed for each main part. The flight path generation system according to item 5, wherein the processing device determines the offset amount for each main section according to the measured wind speed, and updates the flight path by shifting each main section in the opposite direction to the wind direction by the determined offset amount.

[0102] [Item 7] The aforementioned unmanned aerial vehicle can be equipped with a sprayer for distributing granular or liquid agricultural materials to the ground. The flight path generation system according to item 2 or 3, wherein the processing apparatus determines an offset amount for shifting at least one of the plurality of main parts in the opposite direction to the wind direction, taking into consideration at least one of the type, size, and weight of the agricultural material.

[0103] [Item 8] The device further comprises a sensing device for sensing the spraying status of the agricultural material by the sprayer, The sensing device acquires the sensing data indicating the dispersal status after the unmanned aircraft has flown along the updated flight path. The processing device is a flight path generation system according to item 7, which estimates, based on the sensing data, the incomplete areas on the ground where the agricultural material is to be sprayed, out of the total area to be sprayed.

[0104] [Item 9] The flight path generation system according to item 8, wherein the processing device generates a further flight path for spraying the agricultural material over the estimated unfinished area, and causes the unmanned aerial vehicle to fly along the further flight path.

[0105] [Item 10] Multiple rotors, A flight path generation system described in any one of items 1 through 9, An unmanned aerial vehicle equipped with [unspecified] features. [Industrial applicability]

[0106] The unmanned aerial vehicles of this disclosure can be widely used not only for aerial photography, surveying, logistics, and pesticide spraying, but also for ground work related to agricultural operations, and for transporting harvested crops and agricultural materials. [Explanation of Symbols]

[0107] 2...Rotor (propeller), 3...Rotary drive unit, 4...Aircraft body, 4a...Control device, 4b...Sensor group, 4c...Communication device, 5...Aircraft frame, 6...Ground station, 7a...Internal combustion engine, 7b...Fuel tank, 8...Generator, 9...Power buffer, 10...Multicopter, 12, 22...Rotor, 14...Motor, 16...ESC, 76...Power supply unit, 200...Work machine

Claims

1. A flight path generation system mounted on an unmanned aerial vehicle capable of connecting to a sprayer for distributing granular or liquid agricultural materials to the ground, An acquisition device for acquiring data on a predetermined flight path, wherein the flight path includes a plurality of main parts and a plurality of sub-parts, each of which connects the main parts to the other, A sensor that measures wind direction and outputs sensor data indicating the wind direction, A processing device that updates the flight path by shifting at least one of the plurality of main parts to the upwind side according to the wind direction indicated by the sensor data, A sensing device for sensing the spraying status of the agricultural material by the sprayer, Equipped with, The sensing device acquires sensing data indicating the dispersal status after the unmanned aircraft has flown along the updated flight path. The processing device is a flight path generation system that estimates, based on the sensing data, the incomplete areas on the ground where the agricultural material is to be sprayed, out of the total area targeted for spraying.

2. The flight path generation system according to claim 1, wherein each of the plurality of main parts includes a straight section.

3. The aforementioned flight path includes a starting point that causes the unmanned aircraft to begin flying along the aforementioned flight path. The sensor measures the wind direction before the unmanned aerial vehicle passes the starting point. The flight path generation system according to claim 1 or 2, wherein the processing device updates the flight path by shifting all of the plurality of main parts to the upwind side according to the measured wind direction.

4. The aforementioned sensor is configured to further measure wind speed, The flight path generation system according to claim 1 or 2, wherein the processing device determines an offset amount for shifting at least one of the plurality of main parts to the upwind side according to the wind speed.

5. Before the unmanned aerial vehicle begins flying along each of the multiple main parts, the sensor measures the wind speed for each main part. The flight path generation system according to claim 4, wherein the processing device determines the offset amount for each main section according to the measured wind speed, and updates the flight path by shifting each main section to the upwind side by the determined offset amount.

6. The flight path generation system according to claim 1 or 2, wherein the processing apparatus determines an offset amount for shifting at least one of the plurality of main parts to the upwind side, taking into consideration the type, size, and weight of the agricultural material.

7. The flight path generation system according to claim 1, wherein the processing device generates a further flight path for spraying the agricultural material over the estimated unfinished area, and causes the unmanned aerial vehicle to fly along the further flight path.

8. Multiple rotors, A flight path generation system according to claim 1 or 2, An unmanned aerial vehicle equipped with [unspecified] features.

Images